It is common practice in the utility industry to locate transmission line conductors underground, particularly within urban areas. Typically, such electrical conductors are enclosed within an insulating or “cooling” pipe. The pipe carries a dielectric fluid which functions to cool and insulate the electrical conductors which it surrounds. The dielectric fluid, which is often toxic or otherwise environmentally hazardous, is provided under pressure and may be static or circulate throughout “feeder” networks of the cooling pipes. Sensors are often placed throughout the feeder network to detect the pressure, flow, and level of the dielectric fluid, ground ambient temperature, and current loading of the electrical conductors.
Leaks of the hazardous dielectric fluid can occur within the feeder networks due to corrosion of the cooling pipes, valve leaks, or faulty operation. In order to minimize environmental degradation, it is desirable that actual or imminent leaks of such fluid be quickly detected, located and the feeder network repaired. Although the sensors throughout the feeder network may potentially be utilized in detecting such leaks, it is often relatively difficult to distinguish between sensed conditions indicative of leakage and other operational effects.